Danny has had a sister for a few years now, and he would recommend it to anyone. Having rescued Sapphire from the weird misandric cult in which she was raised, turning her into a vampire, moving back from America to Australia, and introducing her to his beloved cousins and/or brother and sister, life is treating both children quite well. Danny's made a killing on the stock market, and he and Sapphire have been constructing a treehouse of the mind using her telepathic magic.
At the moment, the two of them are building an actual treehouse. With wood and stuff.